Second hint to puzzle 88: Nested radicals
- A function, f, such that f(f(x)) =
, is f(x) = 
. A solution to f(x) = x, if it exists, will also be a solution to f(f(x)) = x. - To solve f(x) = x, consider the substitution y =
.
, is f(x) = . A solution to f(x) = x, if it exists, will also be a solution to f(f(x)) = x..